President Obama speaks at a Father's Day luncheon. / Pool photo from Getty Images

by Aamer Madhani and David Jackson, USA TODAY

by Aamer Madhani and David Jackson, USA TODAY

WASHINGTON - President Obama traveled a long and tortured path before coming to the conclusion that it was necessary to provide direct military aid to Syrian rebels trying to topple Bashar Assad's regime.

Now that he's agreed to send small arms and ammunition to the main rebel group, the Supreme Military Council, the way forward may become more difficult.

Even as lawmakers on both sides of the aisle increasingly call on Obama to decisively back the rebels, the president is clear-eyed that the road to an endgame could involve the sort of messy, long and complicated engagement he's tried to avoid.

The president's first big test on his Syria policy - after the White House's announcement that it was highly likely Assad deployed chemical weapons against the opposition - comes Monday when Obama meets with Russian President Vladimir Putin on the sidelines of the Group of Eight summit in Northern Ireland.

"They don't want to see a downward spiral. They don't want to see a chaotic situation in the region," said White House Deputy National Security Adviser Ben Rhodes. "It's in Russia's interest to join us in applying pressure on Bashar al-Assad in a way that relinquishes his power and stature in Syria."

The Russians, along with Iran and Hezbollah, have provided Assad's regime with mortars, light artillery, antiaircraft guns, antitank weapons and ammunition.

As Obama tries to convince Russia to give up Assad, lawmakers are increasingly pushing for the president to at least provide the same level of weaponry Russia has provided Assad's forces.

Sen. Robert Casey, D-Pa., told USA TODAY that the United States should launch cruise missile strikes to ground the Syrian air force and create a safe zone for rebels. Other lawmakers have called for establishing a no-fly zone.

"We have to do something substantial now," Casey said.

Obama remains concerned about providing sophisticated weaponry to the rebels out of fear that they could end up in the hands of al-Qaeda-aligned fighters among the rebels. It remains unclear what, if any, high-end weaponry he's willing to give the rebels.

The White House has shown little appetite for establishing a no-fly zone, something Rhodes said cannot be a" silver-bullet" in a war in which Syrian rebels and Assad's forces are in a block-by-block fight.

Anthony Cordesman, a Middle East analyst at the Center for Strategic and International Studies, said the administration certainly faces great risks in arming the rebels. Cordesman said the "grim reality" is that the Syrian civil war is part of a far broader power struggle that threatens to cause convulsions throughout the region.

This crucial moment in the administration's Syria policy comes as Obama's national security team begins a personnel reshuffling that will include the elevation of aides who would seem more open to U.S. intervention and the departure of National Security Adviser Tom Donilon, a consistent voice of caution inside the White House when it comes to Syria. He is set to leave the administration in the coming weeks.

Newly appointed National Security Adviser Susan Rice, who worked for the State Department during Bill Clinton's presidency, has often expressed regret that the United States did not do more to prevent genocide in Rwanda.

Samantha Power, a former National Security Council aide to Obama who has been nominated to replace Rice as U.S. ambassador to the United Nations, made her name as a journalist writing about genocide and the need for a more activist United States and United Nations.

Rice and Power were among those who supported the White House backing NATO-led operations in Libya in 2011 before the ouster of Moammar Gadhafi.

Obama arrives at this moment on Syria after a long history of skepticism that American action can make a difference in the situation on the ground.

As the Arab Spring took hold in the Middle East and North Africa in early 2011, the administration was relatively quick to declare that the ouster of strongmen Zine Abbidine Ben Ali in Tunisia, Hosni Mubarak in Egypt, Ali Abdullah Saleh in Yemen and Gadhafi in Libya were necessary.

But as popular protests spread through Syria in March 2011, the administration initially resisted calls from hawks such as Sens. John McCain, R-Ariz., Lindsey Graham, R-S.C., and Joe Lieberman, I-Conn., who wanted to see the president take a hard line on Assad

"There's a different leader in Syria now," said then-Secretary of State Hillary Rodham Clinton in late March 2011 - comments that drew the ire of some Republicans. "Many of the members of Congress of both parties who have gone to Syria in recent months have said they believe he's a reformer."

In April 2011, Obama signed the first in a series of executive orders targeting Syrian officials involved in human rights abuses with sanctions.

It wasn't until the middle of August 2011 that Obama, in coordination with other European leaders, called on Assad to resign.

A year later, Obama declared that the use of chemical weapons by Assad's regime would cross a "red line" that would trigger stronger U.S. action.

As recently as a few weeks ago, in the aftermath of initial intelligence reports that it was likely Syria used chemical weapons, Obama struck a cautious tone about the way forward.

"When we rush into things, when we leap before we look, then not only do we pay a price, but oftentimes we see unintended consequences on the ground," Obama said. "So it's important for us to do it right."

Now comes the difficult task of figuring out just what being "right" means.